JPS5926403Y2 - Negative pressure generation valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a negative pressure generating valve that uses compressed air to generate a vacuum or negative pressure within a suction cup.

In general, the second type of negative pressure generating valve switches compressed air from a pressure source C through a stop valve S air filter F and reduced to a constant pressure by a pressure reducing valve R, as shown in the circuit diagram shown in Figure 1. A plurality of branch pipes L1. L2. L3
It is installed inside the suction cup A, and is used to generate negative pressure in A2 and A3 to suction and convey the object W to be suctioned.
Individual negative pressure generating valve V1. v2. The degree of vacuum generated in V3 tends to differ, and the object to be attracted cannot be reliably attracted and conveyed in some cases.

For this reason, as a result of various experiments, the applicant found that such a negative pressure generating valve can maintain a certain supply pressure P as shown in FIG.
It was found that the noise level was the lowest at the supply pressure P1, which produced the best degree of vacuum, as shown in FIG. 3.

In view of the results of such experiments, the present invention aims to easily generate the best degree of vacuum without being affected by the installation location, etc.

For this reason, in the present invention, a pressure reducing valve mechanism is arranged on the compressed air supply side of the throttle hole provided in the valve body, and is integrated with the valve body to control the pressure reduction of the supplied compressed air to a constant pressure. Air is regulated to be optimally adapted to negative pressure generation and is supplied to the throttle hole.

Hereinafter, one embodiment of the present invention will be described based on FIG. 4.

Reference numeral 1 denotes a valve main body, which has an insertion hole 2 formed from one end, and in order to form a throttle valve mechanism described below, the insertion hole has different diameter communication holes 4 and 5 having a tapered portion 3 that becomes a discharge hole. A guide member 6 having a hole therein is inserted and fixed.

7 is a piston having a throttle hole 8, which is slidably inserted into the different diameter flow hole 5 to form a valve chamber 9 between it and the guide member 6; and form an orifice H.

The large diameter portion 10 provided at one end of the piston comes into contact with the end surface of the guide member 6 to regulate the minimum opening degree of the orifice H, and the orifice H is fully opened by the elastic force of a spring 11 installed in the valve chamber 9. It is said that

The valve chamber 9 communicates with a suction hole 14 of the valve body 1 via a communication hole 12 and an annular groove 13 provided in the guide member 6.

The following describes a pressure reducing valve mechanism that is integrated with the negative pressure generating valve to reduce the compressed air introduced into the throttle valve mechanism to a constant pressure, and 15 is a pressure chamber formed in the valve body 1. , is provided in communication with the circulation hole 5 into which the piston 7 is slidably inserted, and furthermore, a hole 18 having a threaded portion 17 is formed between it and the compressed air supply hole 16 .

A valve seat member 21 is screwed into the threaded portion 17 of the hole 18, which is threaded on the outer periphery and further has a passage 19 and a communication hole 20 bored therein so as to communicate the supply hole 16 and the pressure chamber 15. has been done.

Reference numeral 22 denotes a diaphragm which isolates the pressure chamber 15 from the outside. Its center part is sandwiched between a spring receiver 23 and a diaphragm retainer 24, and its outer edge part is fixed to the valve body 1 by a cover 25.

A spring 26 is installed in a spring chamber 27 formed in the cover 25 and applies its pressing force to the diaphragm 22 via the spring receiver 23 . It abuts and is locked.

28 is a poppet member that is slid into a sliding hole 29 formed in the valve body 1 so as to have the same diameter as the passage 19 of the valve seat member 21, and has a spring chamber 30 formed between it and the valve body 1; The poppet member is pressed in the direction of contact with the valve seat member 21 by the pressing force of the spring 31 installed in the spring chamber 30, but the orifice A is pressed by the rod 32 installed between it and the diaphragm retainer 24. The maximum opening is regulated.

33 is a communication hole that communicates the secondary pressure downstream of the orifice A with the spring chamber 30.

The pressure reducing valve mechanism having the above configuration is installed between the supply hole 16 and the aforementioned throttle valve mechanism.

Note that Pg is a connection port for connecting a pressure gauge that detects the pressure of the air that has been reduced in pressure by the pressure reducing valve mechanism and is supplied to the throttle valve mechanism.

Reference numeral 34 denotes a suction cup made of synthetic rubber or the like, which has an action chamber 35 inside and is formed into a cup shape to suction an object to be sucked 36, and has a suction surface 37 formed on the edge of the opening side. The mounting member 38 provided on the opposite side is inserted into the protrusion 39 of the valve body 1, and the fixing member 40 is screwed onto the valve body 1, thereby being fixed.

A check valve mechanism described below is provided between the suction hole 14 and the action chamber 35 of the suction cup 34.

That is, 41 is a valve seat member screwed onto the fixing member 40, which forms a valve chamber 42 between the valve seat member 41 and the valve seat 44 with a gasket 43 attached facing the valve chamber. There is.

A valve rod 45 has one end slidably inserted into the sliding hole 46 of the fixed member 40 and the other end protruded from the valve seat member 41 so as to be movable up and down, and a spring 47 installed in the valve chamber 42. The valve surface 48 is pressed against the valve seat 44 with a pressing force of .

49 is a communication passage that constantly communicates the suction hole 14 and the valve chamber 42;
0 is the valve chamber 42 and the action chamber 3 of the suction cup 34 when the valve stem 45 rises.
This is a communication path for communicating 5.

Further, a protective member 51 made of an elastic material such as synthetic rubber is fixed to the tip of the valve stem 45 in order to protect the surface of the object to be sucked 36, and the tip is provided so as to protrude from the suction surface 37 of the suction cup 34. It is being

Figure 5 is a circuit diagram of an adsorption device constructed by enclosing the negative pressure generating valve (■) of the present invention consisting of the aforementioned throttle valve mechanism and pressure reducing valve mechanism with a chain line, and further providing a plurality of similar valves. This is the same as shown in FIG.

Next, the operation of the above embodiment will be explained.

When compressed air is not introduced into the supply hole 16, each member is in the state shown, but the switching valve is switched and the supply hole 16
When compressed air is introduced into the hole 18 and the passage 19
, the communication hole 20 , the pressure chamber 15 , the throttle hole 8 of the piston 7 , the different-diameter communication hole 4 , and the tapered portion 3 to be discharged to the outside.

At this time, a pressure difference is generated between both end faces of the piston 7 due to the action of the throttle hole 8, and the piston deflects the spring 11 and is displaced to the position indicated by the chain line in the figure, where the large diameter portion 10 comes into contact with the end face of the guide member 6. .

The orifice H is formed with a minimum opening degree, and the suction hole 1 is communicated with the valve chamber 9 by the high-speed flow flowing through the throttle hole 8.
The air inside 4 is sucked into a negative pressure state.

Due to the negative pressure in the suction hole 14, the valve stem 45 of the check valve mechanism receives a force in the upward direction and tries to rise, but the valve surface 48 of the valve stem is forced by the force of the spring 47 to close the valve on which the packing 43 is installed. seat 4
4, the suction hole 14 and suction cup 3
The working chamber 35 of No. 4 is blocked.

When the suction cup 34 is positioned above the suction object 36 and further lowered to come into contact with the suction object 36 by actuation of an actuating device (not shown), the valve stem 45 of the check valve mechanism is moved to the suction cup. 3
Since the valve stem protrudes beyond the suction surface 37 of the suction hole 14, the valve stem first comes into contact with the suction target 36 and bends the spring 47, thereby communicating the suction hole 14 and the action chamber 35.

After that, the suction surface 37 of the suction cup 34 comes into contact with the object 36 to be attracted, and the inside of the action chamber 35 becomes a vacuum state, and the object 36 to be attracted
is attracted and conveyed by the actuating device.

When the conveyance is completed, the switching valve is operated to cut off the supply of compressed air to the supply hole 16 and communicate the supply hole with the atmosphere.The piston 7 is returned to the position shown by the spring 11, and the orifice H is opened to its maximum opening. Then, the atmosphere flowing through the onofice H is quickly introduced into the action chamber 35 through the suction hole 14, the communication passage 49, the valve chamber 42, and the communication passage 50, and the adsorbed object 36 is removed.

When the adsorbed object 36 is removed, the valve stem 45 of the check valve mechanism is lowered by the pressing force of the spring 47, and the valve surface 48 is brought into contact with the valve seat 44 of the valve seat member 41.

Since a pressure reducing valve mechanism is provided between the throttle valve mechanism and the supply hole 16, the compressed air introduced into the throttle valve mechanism is subject to pressure fluctuations in the pressure source C, pressure drop in the pipe line due to piping, and due to the switching valve. Even if there is a pressure drop, the pressure is always maintained at a constant level.

That is, even if the compressed air supplied to the supply hole 16 fluctuates, the pressure on the downstream side of the orifice A formed by the valve seat member 21 and the poppet member 28 remains
0 into the pressure chamber 15 to act on the diaphragm 22 in the pressure chamber, and flow into the spring chamber 30 of the poppet member 28 through the communication hole 33 to act on the lower end surface of the poppet, causing the spring 26 to The poppet member 28 is deflected to a position equal to the pressing force of the spring, and the opening degree of the orifice A is controlled to maintain a constant pressure.

Therefore, the pressure introduced into the throttle valve mechanism is
6, and the spring 26 should be selected so that the throttle valve mechanism generates the best degree of vacuum as shown in FIG. 2 and has a pressure with the least noise.

When an adsorption device is configured using a plurality of negative pressure generating valves as shown in FIG. 5, branch pipe L1. Even if there are different pressure drops between L2 and L3, and even if valves of different sizes are used depending on the shape of the object to be adsorbed, each valve is configured to achieve the optimal degree of vacuum and low noise. can.

In addition, the check valve mechanism isolates the valve chamber 42 of the throttle valve mechanism, which is in a vacuum state when no object is being attracted, from the action chamber 35 of the suction cup 34, and is activated when the valve stem 45 rises during suction. This is to quickly bring the inside of the chamber 35 into a vacuum state to speed up the suction work, and to further prevent the generation of noise.

FIG. 6 is a longitudinal cross-sectional view showing another embodiment of a negative pressure generating valve constructed using a piston-type pressure reducing valve as a pressure reducing valve mechanism. A valve mechanism is constructed, but since it is the same as in the previous embodiment, detailed explanation will be omitted.

55 is an annular groove bored in the valve body 52, and the annular groove communicates with the insertion hole 53 and with a compressed air supply hole 56 provided from one end of the valve body 52 through a communication passage 57. There is.

A piston 58 is slidably inserted into a sliding hole 59.60 formed in the valve body 52 and the guide member 54, and the large diameter portion 61 of the piston is inserted into the orifice B between the valve body 52 and the guide member 54.
is formed.

Reference numeral 62 denotes a pressure chamber formed by inserting the piston 58 into the insertion hole 60, and the pressure chamber includes the orifice B and the communication hole 6.
3.

A spring 64 is installed in a spring chamber 65 formed when the piston 58 is inserted into the sliding hole 59, and applies a pressing force to the piston 58 to press it to a position where the large diameter portion 61 comes into contact with the end surface of the guide member 54.

A hole 66 communicates the spring chamber 65 with the atmosphere.

Next, the operation of the above embodiment will be explained.

When compressed air from a pressure source is introduced into the supply hole 56, the compressed air flows into the pressure chamber 62 through the communication passage 57, the annular groove 55, the orifice B, and the communication hole 63, and flows into the throttle valve mechanism.

The piston 58 receives secondary pressure downstream of the onofice B in the pressure chamber 62, and moves under the pressure of a spring 64 at the other end, thereby controlling the orifice B to keep the secondary pressure constant.

The pressure supplied to the throttle valve mechanism by this compressed air reduced to a constant pressure is maintained constant even if the supply pressure fluctuates due to pressure drop in the pressure source or piping, etc., and the same effect as in the previous embodiment is achieved. can play.

In this way, the present invention has a pressure reducing valve mechanism that controls the pressure reduction of the supplied compressed air to a constant pressure, which is integrated with the valve body and placed on the supply side of the compressed air to the throttle hole that generates negative pressure. The supplied compressed air is regulated to a constant pressure to best adapt to pressure generation, so it is not affected by the installation location, etc.
It can easily generate the best degree of vacuum, strengthen the suction force of the suction cup, and provide reliable suction action.
Noise generation can be reduced.

In addition, the pressure reducing valve mechanism allows the compressed air supplied to the throttle hole to be easily adapted to the generation of negative pressure and to maintain it reliably, resulting in savings in air consumption.

[Brief explanation of drawings]

Figure 1 is a circuit diagram of an adsorption device using a conventional negative pressure generating valve.
Figure 2 is a graph showing the relationship between the supply pressure and vacuum level of a conventional negative pressure generating valve, Figure 3 is a graph also showing the relationship between supply pressure and noise level, and Figure 4 is a graph showing the relationship between the supply pressure and the vacuum level of a conventional negative pressure generating valve. A vertical cross-sectional view of a suction cup attached to a pressure generating valve, Fig. 5 is a circuit diagram of a suction device using a negative pressure generating valve according to the present invention, and Fig. 6 is a vertical cross-sectional view of a negative pressure generating valve showing another embodiment. It is a diagram. 1.52... Valve body, 8... Throttle hole,
9... Valve chamber, 16, 56... Supply hole,
34... Suction cup, 35... Action chamber.

Claims (1)

[Scope of utility model registration request] A throttle hole is provided in the communication path that communicates between the supply hole and the discharge hole of the valve body to increase the flow velocity of the supplied compressed air, and the opening of the throttle hole through which the compressed air is discharged at an increased speed is provided with a suction hole that communicates with the inside of the suction cup. is opened, and a pressure reducing valve mechanism is disposed integrally with the valve body on the supply side of the compressed air to the throttle hole to control the pressure reduction of the supplied compressed air to a constant pressure, and the pressure reducing valve mechanism generates negative pressure in the supplied compressed air. A negative pressure generating valve that is regulated to be optimally adapted to.